Trans-septal catherization procedures typically involve insertion of a needle, such as the trans-septal needle of Cook Incorporated (Bloomington, Ind., USA) into a patient's heart. The needle comprises a stiff metal cannula with a sharpened distal tip. The needle is generally introduced through a dilator and guiding sheath set in the femoral vein and advanced through the vasculature into the right atrium. From there the needle tip is positioned at the fossa ovalis, the preferred location on the septum for creating a puncture.
A trans-jugular approach, using a needle to gain trans-septal access, is described by Joseph et. al. (1997). Joseph states that trans-jugular septal puncture may find application in cardiac electrophysiology because it offers a more direct approach to the mitral annulus, left ventricle, and inferior aspect of the left atrium. In another publication by Joseph et. al. (2000), the author states that in transvenous mitral valvuloplasty, the jugular approach simplifies septal puncture and mitral valve crossing in patients with a huge left atrium and distorted anatomy, besides making the procedure feasible in the presence of obstruction of the inferior vena cava. However, needle trans-septal punctures from the jugular approach are more difficult to perform and require significant practice. Cheng (2003), commenting on the aforementioned articles, states that the transjugular approach for trans-septal needle puncture is more difficult to perform than the transfemoral approach and that only with larger studies and more experience will we be able to tell whether the innovative tranjugular approach is as versatile, efficacious, and safe as the conventional transfemoral approach.
The SafeSheath® CSG Worley, described in the publication entitled “Using the Pressure Products SafeSheath CSG Worley with Radio Opaque Soft-Tipped Braided Core” is a surgical sheath designed to be introduced into a patient's heart through the Superior Vena Cava (SVC) and on through the coronary sinus. The SafeSheath® device is not intended or structured to allow for perforation of patient material nor is it structured to allow for positioning within a patient's heart for perforation and/or dilation.
U.S. Pat. No. 7,056,294 to Khairkhahan et al discloses a method that uses mechanical force to gain transseptal access. The method includes positioning a needle against material and mechanically advancing the needle to gain transseptal access. In one particular embodiment, the tip of a sheath-dilator-transseptal needle combination is placed in the desired location against the fossa ovalis and the transseptal needle is abruptly advanced to accomplish a quick puncture. The needle preferably comprises a tubular structure such as a stainless steel hypotube having a sharpened distal end. Some embodiments include additional mechanical advancement means such as cutting edges or a corkscrew thread. The disclosed method does not include using RF energy to perforate the septum and gain transseptal access.
U.S. Pat. No. 6,814,733 to Schwartz et al includes a method of ablation to create circumferential lesions in the myocardial sleeve of the pulmonary vein to block electrical propagation between the pulmonary vein and the left atrium. Schwartz teaches conventional mechanical needle perforation of the interatrial septum. The method includes a needle and guide-wire crossing the septum before an energy delivery coil. Optionally, as a substitute for using a dilator, the coil can be energized for ablation of septal tissue to ease the passage of a catheter through the septum. This method can include using energy to enlarge an already existing perforation in a septum, but it does not include using energy to perforate a septum. The method's preferred approach to the heart is from an inferior direction.